IL is one year behind in assessing taxes. so the 2020 taxes are payable in 2021.
since you only owned the property for the later part of 2020, you got a credit for the taxes you'll pay in 2021 for the portion of 2020 you did not own the house. so your2021 RE tax deduction is the amount you paid in 2021 for 2020 less the credit you received.
When you get to the state Turbotax should ask four questions about your Illinois property taxes. they all must be answered yes, for the amount enter the net paid, you also need to enter your county and property tax number(s).
if your Illinois adjusted gross income is more than #250,000 you lose the credit.
